Timber Decking Joists

Timber decking joists are the structure upon which your deck boards should be laid. The joists are usually supported by beams which are attached to posts, thus creating a raised deck. Alternatively, you may also ask us for adjustable pedestals upon which you directly lay the joists.

Using high quality timber decking joists are vital to ensuring that your decking lasts for many years and doesn’t start to bend, sag and subsequently begin to rot or even collapse over time. Determining the joist’s strength, durability and spacing can be vital to the success or failure of your decking project.

Whilst timber decking joists are the element of the decking project that you don’t see, they are in fact one of the most important parts of the decking structure. However, many projects assume that because the joists are never seen, there’s no need to pay attention to their specification and therefore end up buying cheaper non-durable softwood options which could also jeopardise the safety of the decked area in just a few years. What’s more, together with the hassle and labour, the cost of replacing rotting joists includes lifting all those beautiful hardwood deck boards and potentially damaging them in the process.

As a general rule, go for joists that are as durable as possible. This will usually mean going for timber that is suitable for Use Class 3 or Use Class 4. If pressure treated, please ask for service life guarantees. Ecochoice can also supply you with dense, strong and durable FSC® certified joists in a range of species to help the longevity of your decking project. By focusing on their performance instead of looks, we can deliver you with alternatives that will also be very cost effective.

The distance between the joists will also ensure your deck area is stable and safe to walk. Here’s an example of span tables for C16 softwood: